Brief Answer:
could be the flu

Detailed Answer:
Hello,

I can't diagnose anything from afar - obviously. I can only comment on your case and suggest appropriate action according to my opinion. A sudden onset is very much in favor of influenza. Vaccination does not provide 100% protection because this virus evolves very fast and may change its genome within the same year (so the vaccine is rendered useless) and also because there are many types of this virus but the vaccine contains only the viruses suspected to cause an epidemic. And even if the vaccine does contain the involved virus, the protection is not 100%.

Having a runny and stuffy nose is usually in favor of a viral illness although no symptom is 100% certain to distinguish between viral and bacterial infection. This distinction is important because viral illnesses (except influenza) cannot be treated with antivirals. Bacterial infections can be treated with antibiotics and influenza can be treated with antivirals.

Things to watch out for include the following as they may denote serious disease or require antibiotic treatment:
- shortness of breath
- low blood pressure and faintness
- unusually low urine output
- confusion
- pleuritic pain
- significant headache

If you don't have any of the aforementioned symptoms then it's very likely that this infection is a common viral respiratory tract infection that will get better by itself.

In any case clinical examination by your primary care physician wouldn't go amiss as the doctor may eliminate diagnostic possibilities and perhaps suggest treatment (for influenza or other infections). Note that patients over 65 years of age should be treated with antivirals when influenza is a serious consideration.

Regarding symptom relief you can use paracetamol (acetaminophen) for the fever and malaise and combinations of antihistamines and decongestants for the nasal symptoms (unless contra-indicated for some reason).

I hope you find my comments helpful!
Kind Regards!

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